EFFECT OF SALINITY ON IN VITRO GROWN POTATO EXPLANTS AND POTENTIAL PROTECTION BY JASMONIC ACID

Solanum tuberosum cv. Kennebec explants grown in vitro in a ½ MS media, with and without 1 mg•L^-1 of JA, were subjected to 5 NaCl treatments. Vegetative development was analyzed, and proline accumulation was determined and used as a salt tolerance marker. The lower NaCl treatment, 30 mM, significantly increased root length, while higher salinity concentrations did not significantly affect root length. Nevertheless, salinity was more harmful for root than for shoot development, since the contribution of the root to the plantlet total dry weight decreased as the NaCl concentrations in the culture media increased. Low salinity level of 30 mM NaCl significantly increased plantlet leaf area, whereas higher concentrations decreased it. For any of the salinity concentrations tested, the addition of JA to the culture medium resulted in a moderated but consistent reduction in proline, suggesting a putative role of jasmonate on salinity stress. Further work is needed on this aspect.